Furthermore, an installation to remove materials to be sieved from a liquid, especially sewage, is suggested, in which case the installation comprises a sieve drum at least partially immersed in the liquid that can be moved around a rotating axis with the help of a drive while the device is being operated that has an opening at least in the front side area so it can be refilled with the liquid that carries the material to be sieved, and in which case the installation has at least one discharge mechanism partially arranged inside the sieve drum for the material to be sieved, preferably in form of a screw conveyor or suction device, in which case the discharge mechanism has a supply area inside the sieve drum in form of a collecting funnel, for example, for the material to be sieved.
Such a corresponding installation is known, for example, from DE 34 20 157 C1. The installation described therein has a sieve drum shaped like a cylindrical shell placed obliquely in a sewer that is hydraulically open on the inflow side (i.e. in opposite flowing direction of the sewage flowing into the sewer) and is largely hydraulically closed on the outflow side. The sieve drum has, for example, slots that form a separation surface on the inner side for the material to be sieved that is carried by the sewage, in which case the liquid passes through the slots and thus stays in the sewer. Finally, the sieve drum is driven in a rotating manner together with a screw conveyor protruding partially into the sieve drum, in which case the screw conveyor begins in the area of a collecting funnel for the material to be sieved that is arranged inside the sieve drum. Above the collecting funnel, in the outer side area of the sieve drum, a removal mechanism arranged immovably in form of a brush roller or spray water bar is provided to remove the material to be sieved adhering to it from the outside. Finally, the material to be sieved falls into the collecting funnel, from which it can be transported by the screw conveyor (installed subsequently) to a dropping place located outside the sewer.
Generally, in connection with the above-mentioned sieve drum, it is customary to weld the sieve plates that form the sieve wall together or with a sieve drum support structure to give it the necessary stability. However, the heat generated by the welding process can produce localized sieve drum unbalances that in the later operation of the installation could lead to increased wear when the sieve drum is rotated.